Title: Real-space imaging of periodic nanotextures in thin films via phasing of diffraction data

Abstract

New properties and exotic quantum phenomena can form due to periodic nanotextures, including Moire patterns, ferroic domains, and topologically protected magnetization and polarization textures. Despite the availability of powerful tools to characterize the atomic crystal structure, the visualization of nanoscale strain-modulated structural motifs remains challenging. Here, we develop nondestructive real-space imaging of periodic lattice distortions in thin epitaxial films and report an emergent periodic nanotexture in a Mott insulator. Specifically, we combine iterative phase retrieval with unsupervised machine learning to invert the diffuse scattering pattern from conventional X-ray reciprocal-space maps into real-space images of crystalline displacements. Our imaging in PbTiO ₃ /SrTiO ₃ superlattices exhibiting checkerboard strain modulation substantiates published phase-field model calculations. Furthermore, the imaging of biaxially strained Mott insulator Ca ₂ RuO ₄ reveals a strain-induced nanotexture comprised of nanometer-thin metallic-structure wires separated by nanometer-thin Mott-insulating-structure walls, as confirmed by cryogenic scanning transmission electron microscopy (cryo-STEM). The nanotexture in Ca ₂ RuO ₄ film is induced by the metal-to-insulator transition and has not been reported in bulk crystals. We expect the phasing of diffuse X-ray scattering from thin crystalline films in combination with cryo-STEM to open a powerful avenue for discovering, visualizing, and quantifying the periodic strain-modulated structuresmore » in quantum materials.« less

Authors:

Shao, Ziming ^[1]; Schnitzer, Noah ^[1]; Ruf, Jacob  ^[2];

• Search DOE PAGES for author "Ruf, Jacob"
• Search DOE PAGES for ORCID "0000-0002-4426-2884"

Gorobtsov, Oleg Yu. ^[1]; Dai, Cheng ^[3]; Goodge, Berit H.  ^[4];

• Search DOE PAGES for author "Goodge, Berit H."
• Search DOE PAGES for ORCID "0000-0003-0948-7698"

Yang, Tiannan ^[3]; Nair, Hari ^[1]; Stoica, Vlad A. ^[5]; Freeland, John W. ^[6]; Ruff, Jacob P. ^[7]; Chen, Long-Qing ^[3]; Schlom, Darrell G.  ^[8];

• Search DOE PAGES for author "Schlom, Darrell G."
• Search DOE PAGES for ORCID "0000-0003-2493-6113"

Shen, Kyle M. ^[9]; Kourkoutis, Lena F.  ^[4];

• Search DOE PAGES for author "Kourkoutis, Lena F."
• Search DOE PAGES for ORCID "0000-0002-1303-1362"

Singer, Andrej  ^[1]

• Search DOE PAGES for author "Singer, Andrej"
• Search DOE PAGES for ORCID "0000-0002-2965-9242"

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+ Show Author Affiliations

1. Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853
2. Department of Physics, Cornell University, Ithaca, NY 14853
3. Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802
4. School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853
5. Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802, Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439
6. Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439
7. Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14853
8. Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853, Leibniz-Institut für Kristallzüchtung, Berlin 12489, Germany
9. Department of Physics, Cornell University, Ithaca, NY 14853, Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853

Publication Date:

Thu Jul 06 00:00:00 EDT 2023

Sponsoring Org.:

USDOE

OSTI Identifier:

1988331

Grant/Contract Number:  

SC0019414; AC02-06CH11357; SC0020145; SC-0012375

Resource Type:

Published Article

Journal Name:

Proceedings of the National Academy of Sciences of the United States of America

Additional Journal Information:

Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Volume: 120 Journal Issue: 28; Journal ID: ISSN 0027-8424

Publisher:

Proceedings of the National Academy of Sciences

Country of Publication:

United States

Language:

English